On a recent trip out our 1937 Rover 12 Sports Saloon played up a little on the way back, coughing and spluttering and down on power, so we had to stop a few times to try and diagnose the problem, but to no avail. However, she did eventually clear herself and we made it back OK.
I suspected it may be dirt in the fuel and indeed the fuel filter was an old plastic type one and showing that it had indeed collected some stuff. I therefore, replaced that with a new glass one and also checked the fuel pump filter, which was clean, and fitted new spark plugs.
She started up straight away, as she always has done, and I promptly got ready for a test drive to see if she was still a little hesitant. However, after leaving her to warm up I came out to find she had stopped…….and she now will not restart (turns over but does not fire). Upon checking the float bowl it was not full and so I thought maybe she had run out of fuel, despite the fuel gauge reading a quarter of a tank. So more fuel in, but still not desire to fire.
So any ideas on what might be going on and perhaps where to check next?
The car has electronic ignition so I am assuming that is not the cause.
And a quick question, reference the jet adjusting nut on the SU carb, which direction weakens the mixture, clockwise (screwing it in) or anti-clockwise (screwing it out)?
Starting Problems
Re: Starting Problems
OK, the problem seems to have solved itself after establishing that it was lack of fuel feed from the tank as the car started and ran OK with the float bowl filled, but the fuel pump was still dry.
So having worked back to where the rubber fuel pipe connected to the metal feed line, I blew through the line and also rodded it with wire back as far as I could. Now she starts and runs OK but I am still nervous about what caused it and presumably there is still the treat that it will happen again and maybe not in the driveway this time!
So next task is to try and blow the metal fuel line through from the tank end, but am not sure where best to get access. Any ideas?
So having worked back to where the rubber fuel pipe connected to the metal feed line, I blew through the line and also rodded it with wire back as far as I could. Now she starts and runs OK but I am still nervous about what caused it and presumably there is still the treat that it will happen again and maybe not in the driveway this time!
So next task is to try and blow the metal fuel line through from the tank end, but am not sure where best to get access. Any ideas?
1937 Rover 12 Sports Saloon
Re: Starting Problems
Turning the nut up, ie to the right, weakens the mixture, the reverse being true for enriching.it.
On the 37 car you have, I am presuming you have an access hatch in the boot floor to the fuel pipe pick up. Have you an electric reserve or a mechanical switch for it? Either way it should be easy ish to disconnect the fuel pipe at the tank end to blow through it. However, you also need to blow through the tank pick up unit, both pipes. The likely culprits are large pieces of debris which have gathered in the bottom of the tank. The suction pulls them to the pick up pipe, they get pulled to it , stay there then fall off when the suction stops. It can be worthwhile to drain the tank through the plug on the bottom ,filter the petrol, refill with a gallon, drive a little, repeat the process. In extreme cases, remove the tank, clean out as far as possible, remove the sender unit and pick up pipe and fill with POR tank sealer from Frost. This will seal in any loose pieces of rubbish you cannot otherwise remove.
Only personally, I do not share your faith in electronic ignition units. I reckon they work reliably until they fail. I would carry a baseplate with a condenser and points ready to fit if required as a back up
However, given you have what you have, it is my belief that people fit electronic ignition without necessarily having fully explored the many potential minor failings in the rest of the ignition circuit. The electronic module may remove a worn condenser and worn points but the weak points in the DK distributor, if that is what your car has, can start with a failing coil - possibly overheated at some previous time, poor HT leads or a poor LT lead , broken insulation in the system somewhere, such as baseplate cracks, cap cracks, rotor arm failings (particularly with riveted arms) and also potentially whether you have a plug lead cover fitted or not. Also check for sideways play in the distributor shaft due to potentially worn bushes.
It can be worthwhile running the engine in the dark and looking to see whether there are any signs of sparking visible, where something is jumping to earth.
There are useful little gadgets available for testing spark intensity. I can't put a link on tonight but will do so tomorrow. They are only £5-£6 from memory. It is worth remembering that annual servicing used to include throwing out the cap, points, condenser, and rotor arm each year to be replaced with new. I have to confess to just having replaced a condenser I previously replaced 14 years ago, after about 5000 miles.
Just going back to the coil a second, it could be worth checking what the maximum voltage in your charging circuit is. Although the amps going in may appear normal, I am aware of too high a voltage in the system - over about 14.4 or so, potentially having a detrimental effect on a tired coil. Just sone things to maybe try over the weekend !
On the 37 car you have, I am presuming you have an access hatch in the boot floor to the fuel pipe pick up. Have you an electric reserve or a mechanical switch for it? Either way it should be easy ish to disconnect the fuel pipe at the tank end to blow through it. However, you also need to blow through the tank pick up unit, both pipes. The likely culprits are large pieces of debris which have gathered in the bottom of the tank. The suction pulls them to the pick up pipe, they get pulled to it , stay there then fall off when the suction stops. It can be worthwhile to drain the tank through the plug on the bottom ,filter the petrol, refill with a gallon, drive a little, repeat the process. In extreme cases, remove the tank, clean out as far as possible, remove the sender unit and pick up pipe and fill with POR tank sealer from Frost. This will seal in any loose pieces of rubbish you cannot otherwise remove.
Only personally, I do not share your faith in electronic ignition units. I reckon they work reliably until they fail. I would carry a baseplate with a condenser and points ready to fit if required as a back up
However, given you have what you have, it is my belief that people fit electronic ignition without necessarily having fully explored the many potential minor failings in the rest of the ignition circuit. The electronic module may remove a worn condenser and worn points but the weak points in the DK distributor, if that is what your car has, can start with a failing coil - possibly overheated at some previous time, poor HT leads or a poor LT lead , broken insulation in the system somewhere, such as baseplate cracks, cap cracks, rotor arm failings (particularly with riveted arms) and also potentially whether you have a plug lead cover fitted or not. Also check for sideways play in the distributor shaft due to potentially worn bushes.
It can be worthwhile running the engine in the dark and looking to see whether there are any signs of sparking visible, where something is jumping to earth.
There are useful little gadgets available for testing spark intensity. I can't put a link on tonight but will do so tomorrow. They are only £5-£6 from memory. It is worth remembering that annual servicing used to include throwing out the cap, points, condenser, and rotor arm each year to be replaced with new. I have to confess to just having replaced a condenser I previously replaced 14 years ago, after about 5000 miles.
Just going back to the coil a second, it could be worth checking what the maximum voltage in your charging circuit is. Although the amps going in may appear normal, I am aware of too high a voltage in the system - over about 14.4 or so, potentially having a detrimental effect on a tired coil. Just sone things to maybe try over the weekend !